1. Field of the Invention
The invention relates to a travel support apparatus, and more particularly to a travel support apparatus that controls travel of a vehicle so as to prevent contact between the vehicle and an obstacle as the vehicle backs up.
2. Description of Related Art
An apparatus that controls travel of a vehicle so as to prevent contact between the vehicle and an obstacle has been proposed. For example, Japanese Patent Application Publication No. 2006-123711 (JP-A-2006-123711) proposes an apparatus that is capable of securing safety even when a driver mistakenly performs an acceleration operation when intending to perform a braking operation. This apparatus includes: a front ultrasonic sensor and a rear ultrasonic sensor each of which detects a distance and a relative speed between the vehicle and an obstacle existing in a moving direction of the vehicle when the vehicle moves forward or backs up; means for detecting an acceleration request amount from the driver of the vehicle; a collision possibility determination unit that determines whether there is a possibility of a collision between the vehicle and the obstacle based on the distance and relative speed between the vehicle and the obstacle detected by the front ultrasonic sensor or the rear ultrasonic sensor; and means for braking the vehicle by recognizing a detected acceleration request as a braking request from the driver when the collision possibility determination unit determines that there is a possibility of a collision.
In the technique described above, however, control is performed to apply a brake to the vehicle every time it is determined that there is a possibility of a collision with the obstacle detected by the front ultrasonic sensor or rear ultrasonic sensor. This may be bothersome to the driver. In particular, with this technique, it is not possible to respond to a situation in which the driver of the vehicle wishes to accelerate the vehicle in order to, for example, move closer to the obstacle. Further, since the control for applying a brake to the vehicle is always performed, the driver may rely too much on the apparatus.